( Reaffirmed 2004 ) IS : 8983 - 1978 Indian Standard SPECIFICATION FOR READY MIXED PAINT, FINISHING, STOVING, FOR WAR EQUIPMENT Paints Chairman SHRI T. K. S. MANI and Allied Products Sectional Committee, Representing CDC 8 Addisons Paints & Chemicals Ltd, Madras Members Shri T. K. S. Mani ) SERI S. K. ASTHANA SHRI S. PANDEY ( Alternate ) SRRI BALJIT SINGH SRRI HARDIP SINGH ( Alternate DR P. K. BHANDARI SHRI N. S. BHARATJA SHRI S. H. DESAI ( Alternate ) SHRI S. BHATTACEARYYA SHRI M. B. SATYANARYANA (Alternate to Ministry of Defence ( DGI ) Bhagsons Paint Industries ( India ), New Delhi ) Shalimar Paints Ltd, Calcutta Blundell Eomite Paints Ltd, Bombay The Alkali & Chemicals Rishra Corporation of India Ltd, SRRI G. N. TEWARI ( Alternate ) Asian Paints ( India ) Ltd, Bombay SHRI C. J. BHUMEAR SHRI P. N. WAGLE ( Alternate ) Oil Technologists' Association of India, Kanpur DR S. CHANDRA SHRI M. S. SAXENA ( Alternate ) All India Small Scale Paints & Allied Industries' SRRI G. L. DEWAR Association, Bombay SHRI AJIT SI&H DRINGRA ( Alternate ) ' The Piemier Automobiles Ltd, Bombay SHRI P. K. DESHPANDE SHRI D. A. PATKI ( Alternate ) Directorate General of Supplies & Dirposalr, SHRI N. G. S. IYER New Delhi JOINT DIRECTOR ( CHEMICAL ), Railway Board, Ministry of Railways RDSO -I)EPIJTY DIRECTOR ( CHEMICAL ), RDSO ( Alternatr ) ( Continued on Page 2 INDIAN @ Copyright STANDARDS 1979 INSTITUTION This publication is protected under the Indian Copyright Act ( XIV of 1957 ) and reproduction in whole or in part by any means except with written permission of the publisher shall be deemed to be an infringement of copyright under the said Act. IS : 8983 - 1978 Representing ( Confinuedfrom page 1 ) Members SHRI R. D. KAWATRA Directorate General of Technical Development, New Delhi SHRI KULTAR SINGR ( Alterante ) Goodlass Nerolac Paints Ltd, Bombay SRRI R. K. MARPHATIA SHRI N. R. KOLWALKAR ( Alternate ) Indian Aluminium Co Ltd, Calcutta SRRI P. N. PHADI~E SHRI M. PHILIP ( Alternate ) Bharat Heavy Electricals Ltd, Tiruchchirappalli SHRI D. RAMAMOORTEY SHRI M. B. UNNI ( Alfernate ) Indian Paint Association, Calcutta SRRI M. N. RAO SHRI M. M. GHOSH ( Alternate) Sudarshan Chemical Industries Ltd, Pune DR R. J. RATHI SRRI K. L. RATHI ( Altertufs ) Development Commissioner, Small Scale Industries, SRRI P. SATYANARAYANAN New Delhi SCIENTIFIC ADVISER TO THE Naval Headquarters, New Delhi CHIEF OF THE NAVAL STAFP National Test House, Calcutta SHRI K. C. SEAL SRRI A. N. ROICHOWDHURY ( Alternate ) Central Building Research Institute ( CSIR ), DR S. M. SINQH Roorkee SR.RI R. S. SRIVASTAVA ( Alternate ) Regional Research Laboratory ( CSIR ), Hyderabad DR M A SIVASA~BAN DR M. M. SHIRSALKAR ( Alternate) SUPERINTENDING STJRVEY~R OF Central Public Works Department, New Delhi WORKS ( I ) SURVEYOR OF WORKS ( Altrrnatc ) Director General, IS1 ( Ex-ojkio Member ) DR G. M. SAXRNA, Director ( Chem ) Secretary SHRI R. K. SIN~H Deputy Director ( Chem ), ISI Panel Conocner DR P. K. BHANDARI Mem bcrs SHRI S. K. ARTR~NA SRRI S. PANUEY ( Alternate ) SHRI R. D. BHATIA DEPUTY DIRECTOR ( CHEMICAL ), RDSO, LUCKNOW SHRI S. S. DHINGRA SHRI N. G. S. I~rn SRRI S. K. BASU ( Alternate ) SHRI T. K. S. MANI SHRI M. N. RAO DR A. B. GERSAPPE (Alternate SHRI A. N. ROICROWDHVRY Ministry of Defence ( DGI ) Kohinoor Paints Pvt Ltd, Amritsar Railway Board ( Ministry of Railways ) U. K. Paints Industries, Amritsar Directorate General of Supplies New Delhi & Disposals, Shalimar Paints Ltd, Calcutta for RMP's, Enamels and Adjuncts, CDC 8 :6 :6 Addisons Paint? & Chemicals Ltd, Madras Indian Paint Association, Calcutta ) National Test House, Calcutta 2 IS:8983 - 1978 Indian Standard SPECIFICATION FOR READY MIXED PAINT, FINISHING, STOVING, FOR WAR EQUIPMENT 0. FOREWORD 0.1 This Indian Standard was adopted by the Indian Standards Institution on 18 October 1978, after the draft finalized by the Paints and Allied Products Sectional Committee had been approved by the Chemical Division Council. 0.2 At present a large number of specifications for paints and allied products, prepared by Directorate of Standardization, Ministry of Defence, Government of India, are in force for procurement of materials On a request from Ministry of Defence, the for use by Defence services. feasibility of aligning specifications prepared by them with the corresponding Indian Standards or preparing separate specification where no such It has now been decided to prepare standard exists has been examined. national standards for commodities which are required in bulk quantities by Ministry of Defence and are also used for other purposes. 0.3 This standard achieves full alignment with JSS 8010-14 Paint, R.F.U. finishing, war .equipment, stoving, brushing/spraying, olive green, issued by the Department of Standardization, Ministry of Defence, Government of India. The material is recommended to be supplied in brushing consistency but shall be suitable for spraying after thinning with a suitable thinner. 0.4 This standard contains clause 6.1 which the purchaser and the supplier. calls for agreement between 0.5 For the purpose of deciding whether a particular requirement of this standard is complied with, the final value, observed or calculated, expressing the result of a test or analysis, shall be rounded cff in accordance with IS : 2-1960*. The number of significant places retained in the rounded off value should be the same as that of the specified value in this standard. *Rules for rounding off numerical values ( revised). 3 IS:8983 - 1978 1. SCOPE 1.1 This standard prescribes requirements and methods of sampling and test for the material commercially known as ready mixed paint, finishing, stoving, for war equipment. The material is used for protection and maintenance of war equipment and also as exterior petrol resisting paint. 1.1.1 The material shall normally be applied over a suitable priming paint ( stoving ) but formulation shall be such as to provide reasonable camouflaging and protection if applied direct on metal. 2. TERMINOLOGY 2.1 For the purpose of this standard, to those given in 2 of IS : lOI-1964* the following definition, in addition and IS : 1303-1963t shall apply. 2.1.1 Registered Sample - Sample supplied in advance by a prospective supplier and registered by the approved testing authority after testing it to all the requirements of this standard. A complete record of its performance shall be kept in respect of all tests. 3. CLASSES 3.1 The material shall be supplied in brushing consistency but shall be suitable for application by spraying after thinning with petroleum hydrocarbon solvent, low aromatic, 1451205 grade conforming to IS : 1745-1978:. 4. COLOUR 4.1 The Standard colour Colour of the material shall be scamic ( olive ( ISC ) No. 294 ( see IS : 5-1978s ). green ) Indian 5. REQUIREMENTS 5.1 Pigment Composition - The dry pigment content of the material shall be 33 f 3 percent by mass. The pigment shall contain minimum 6 percent by mass of green oxide of chromium when determined as prescribed in Appendix A. 5.2 The material Table 1. shall also comply with the requirements prescribed in *Mrthods of test for ready mixed paints and enamels ( second revision ). tGlossary of terms relating to pains ( rsviscd ). fSpecification for petroleum hydrocarbon solvents ( second revision ). §Colour for ready mixed paints and enamels ( third revision ). 4 IS:8983 TABLE 1 REQUIREMENTS STOVING, FOR FOR READY MIXED PAINT, WAR EQUIPMENT -1978 FINISHING, ( Clause 5.2 ) 2. (1) i) ii) CHARACTERISTIC REQUIREMENT METHOD OF TEST, REP TO CL No. IN r--_-A--_-y Appendix IS : lOl1964' (4) (5) 7.4 and 7.4.1 6 (2) Consistency and viscosity ( by flow cup ) Application (3) Smooth and uniform and within f 10 seconds of the registered sample Suitable for application by brushing without appreciable drag on the brush Hard dry and mar resistant film when stoved at 140°C for 23 min Smooth and semiglossy Between -10 percent and the + 20 percent of registered sample Close match colour to specified iii) Drying time 7.1 and 7.3.2 7.5 10 iv) ") vi) vii) Finish Wet opacity Colour Scratch hardness 11 15.1 Bare metal shall not be visible through the scratch under load of 1.5 kg No damage or detachment or cracking of the film There shall be not more than very slight change of colour, not more than rust slight superficial spotting, no blistering of permanent nature ( blistering which does not subside within 24h after removal of the painted panel from the corrosion cabinet shall be termed as permanent ), no brittleness of the paint film and the metal surface underneath the film shall not show any sign of corrosion No sign injury of permanent viii) ix) Flexibility Protection sion and adhesion against corro- - 16 1st x) Resistance oil to lubricating - 19 *Methods of test for ready mixed paints and enamels ( second revision ), tExcept for duration of the test period which shall be 10 days. ( Continued ) 5 IS : 8983 - 1978 TABLE SL No. 1 REQUIREMENTS FOR READY MIXED PAINT, STOVING, FOR WAR EQUIPMENT - Contd REQUIREMENT FINISHING, CHARACTERISTIC METHOIJ OF TEST, REF TO CL No. IN r-_--h____7 Appendix IS : lOl1964* permanent (4) B (5) 22 (1) xi) xii) (2) Resistance to petrol ben201 mixture Resistance to heat (3) No sign injury of NO sign of cracking, blistering and appreciable change of colour when stoved at 150°C for 2 h. In this respect the film shall not be inferior to registered sample test Amount of water absorbed shall not exceed 5 mg/cms of painted surface exposed No fading colour or change of - xiii) Water absorption - xiv) Resistance to warm water at 45 f 3°C for 4h Resistance to salt water xv) No rust spotting, flaking or peeling or any other deterioration of the paint film when examincd at a magnification of 10 diameter To pass the test 30 5 F G 24 xvi) xvii) xviii) Durability Flash point, "C, Min Calcium compounds in the dry pigments ( as percent by CaO 1, mass, Max Barium compounds in dry pigments ( as B&O, 1, percent by mass, MUX Watercontent ( if water is suspected to be present ), percent by mass, MC? Lead restriction Mass in kg/l0 litres Keeping properties, Min xix) 33 H xx) 0'5 14 xxi) xxii) xxiii) Not a lead paint Within f 3 percent of the registered sample The material shall not cake hard inside the containers and shall retain properties for one year from the date of delivery 28 25 - 31 *Methods of test for ready mixed paints and enamels ( second rcuision ). 6 IS : 8983 - 1978 6. PACKING 6.1 Packing AND MARKING purchaser and conforming to - Unless otherwise agreed to between the the supplier, the paint shall be packed in metal containers IS : 1407-1968* or IS : 2552-1970t. 6.2 Marking a) Name - Each container shall be marked and/or with the following: trade-mark, if and colour of the material; his recognized b) Name of the manufacturer any; c) Volume of the material; d) Batch e) Month No. or lot No. in code or otherwise; and year of manufacture. containers may also be marked and 6.2.1 The Mark. with the IS1 Certification NOTE - The use of the ISI Certification Mark is governed by the provisions of the Indian Standards Institution ( Certification Marks ) Act and the Rules and Regulations made thereunder. The ISI mark on products covered by an Indian Standard conveys the assurance that they have been produced to comply with the requirements of that standard under a well-defined system of inspection, testing and quality control which IS1 marked products is devised and supervised by IS1 and operated by the producer. are also continuously checked by IS1 for conformity to that standard as a further safeguard. Details of conditions under which a licence for the use of the IS1 Certification Mark may be granted to manufacturers or processors, may be obtained from the Indian Standards Institution. 7. SAMPLING 7.1 Represent,ative as prescribed under samples of the material 3 of IS : IOl-1964$. shall be drawn and treated to 7.2 Criteria for Conformity - A lot shall be declared conforming the requirements of this standard if the test results on a composite sample satisfy the requirements prescribed in 5. 8. TEST METHODS 8.1 Tests shall be conducted according to the methods prescribed in to the relevant IS : lOl-19641 and Appendices A to H. References Appendices and clauses Table 1 respectively. of that standard are given in co1 4 and 5 of *Specification for round paint tins (fkt revision ). jSpecification for steel drums ( galvanized and ungalvanized ) (fi7Strevision ). iMethods of test for ready mixed paints and enamels ( second revision ). 7 IS : 8983 - 1978 8.2 Quality of Reagents - Unless specified otherwise, pure chemicals and distilled water ( see IS : 1070-1977* ) shall be employed in tests. NOTE - ` Pure chemicals * shall which affect the result of analysis. mean chemicals that do not contain impurities 8.3 For match against Indian Standard colour, IS:5-1978t shall be used. APPENDIX A OF CHROMIUM (CZau.w 5.1) DETERMINATION A-9. GENERAL A-O.1 Chromium oxide ( CrsOs) content of the pigment is estimated from acid insoluble chromium compounds. The method involves the estimation of total chromium compounds as Cr2Os in paint and acid soluble chromium compounds as Cr2Os in pigment of the paint. A-l. REAGENTS A-l.1 A-I.2 A-I.3 A-I.4 Sodium Peroxide Sulpbu~ic Acid Potassium concentrated. Solution 5 percent ( m/v). 10 percent ( m/v). OF GREEN OXIDE Permanganate Silver Nitrate Solution Persulphate Acid Acid - A-1.5 Ammonium A-1.6 Hydrochloric A-l.7 Phosphoric Dilute. Relative density l-7. Solution Solution approximately @ 1 N. IN PAINT Sulphate Permanganate A-l.8 Ferrous O-1 N. A-l.9 Ammonium Standard Potassium A-2. ESTIMATION OF CHROMIUM COMPOUNDS A-2.1 Procedure - Weigh accurately about 1 to 2 g of the paint in a nickel crucible and ignite over a gas flame. Fuse it with 5 g of sodium peroxide over a gas flame, keeping the molten mass at low red heat for 5 minutes. Dissolve the cooled fusion cake in the crucible in 200 ml of *Specification for water for general laboratory use ( second reoision ). ~Colours for ready mixed paints and enamels ( third rbsion ). IS:8983-1978 warm water and transfer the rinsings to a beaker. Add concentrated sulphuric acid to adjust to 10 percent acidity in the solution. Add 4 to 6 drops of 5 percent potassium permanganate solution and 1 to 2 ml of silver nitrate solution. Heat to boil. Add ammonium persulphate till pink colour of potassium permanganate reappears. Add dilute hydrochloric acid just to destroy the pink colour. Boil to expel chlorine. Cool and add 5 ml of phosphoric acid. Add exactly 50 ml of ferrous ammonium sulphate solution with vigorous stirring. A deep green colour develops when reduction is complete. Titrate the excess of ferrous ammonium sulphate solution with standard potassium permanganate solution, taking the first faint darkening of the clear green colour as the end point. Run a blank, starting from peroxide fusion, in the same manner and at the same time. Note the volumes of potassium permanganate solution required in both cases. A-3. ESTIMATION COMPOUNDS OF ACID SOLUBLE IN PIGMENT CHROMIUM A-3.1 Procedure - Weigh accurately about 0.5 to 1 g of the dried pigment of the sample and digest it in 200 ml of water in a covered beaker. Add 25 ml of sulphuric acid. Boil for 10 minutes, cool and filter. Then proceed as prescribed in A-2.1. A-4. CALCULATION A-4.1 Chromium oxide in both the cases as prescribed in A-2.1 and A-3.1 is calculated as follows: Chromium oxide by mass where G-203 percent = ( A - B ) x N x 2'534 M A = volume in ml of potassium permanganate for blank titration, solution required solution B = volume in ml of potassium required in the assay, permanganate Jv = normality of potassium permanganate solution, and M = mass in g of the sample taken for the test. A-4.2 Calculate percent pigment as follows: total CraOs content of total chromium in ( Calculated chromium oxide content in paint ) X ( 100 Percent pigment in the sample of paint ) iS : 8983 - 1978 A-4.3 Calculate acid insoluble chromium Acid insoluble chromium (as CrsOa) in pigment, percent by mass where X = Y = total chromium acid soluble (as Crz03 ) calculated in A-4.2, and in A-3.1. oxide as follows: = X- r chromium oxide as determined APPENDIX B [ Table 1, Item (xi) ] TEST B-l. B-l.1 B-l.2 B-2. FOR RESISTANCE TO PETROL-BENZOL MIXTURE REAGENTS Benz01 pure. Ether boiling range 60 to SO'%, aromatic free. Petroleum PROCEDURE B-2.1 Take a tin plate panel 150 x 50 x 0.315 mm free from surface imperfections, roughen with No. 0 abrasive paper. Apply the paint by brushing in a single coat to give a dry film mass as specified under 6.4 of Stove the paint film at 140°C for 23 minutes. Then IS : IOl-1964*. immerse it in a mixture of 5 parts by volume of benzol and 95 parts by volume of petroleum ether for 5 minutes at room temperature not below 15°C. Examine the paint film for 30 minutes after removal of the panel from the mixture. B-2.2 The material shall be taken to have passed the requirements of this test if the paint film does not show any sign of permanent injury and withstands the scratch hardness test. APPENDIX C [ Table 1, Item (xiii) ] TEST C-l. C-l.1 REAGENTS Paraffin Wax and Beeswax ( 1 : 1 ) Mixture molten. FOR WATER ABSORPTION *Methods of test for ready mixed paints and enamels ( second revision) . 10 IS : 8983 - 1978 C-2. PROCEDURE C-2.1 Thoroughly degrease with a suitable solvent and subsequently amalgamate by mercury a clean tin plate panel 150 x 150 x O-315mm. Apply the paint by brushing in a single coat to give a dry film mass as specified under 6.4 of IS : lOl-1964* and stove it at 140°C for 23 minutes. Allow the painted panel to stand at room temperature not below 15"C, for 24 hours. C-2.2 Seal the edges and corners of the panel by dipping in the molten mixture of paraffin and beeswax and completely immerse in water for 7 days at room temperature, not below 15°C. C-2.3 Remove the panel from water and immediately cut 100 X 50 mm Absorb the loosely adherent moisture on both sides film from the panel. Place the film in a tared weighing tube of the film by blotting paper. Then heat the weighing tube with its contents at 70°C to and weight it. constant mass. The loss in mass shall be the amount of water absorbed. APPENDIX D [ Table 1, Item (xiv) ] TEST D-l. FOR RESISTANCE TO WARM WATER PROCEDURE 150 X 100 x 1.25 mm free from surface imperfections and roughen with No. 0 abrasive paper. Paint the panel and Immerse the panel in keep it under drying conditions prescribed in B-2. Remove the panel, keep at water maintained at 45 f 2°C for 4 hours. room temperature for 1 hour and examine the dried paint film for any fading or change in colour. D-l.1 Take a mild steel plate, APPENDIX E [ Table 1, Item (xv) ] TEST FOR RESISTANCE E-l. E-l.1 E-1.2 E-l.3 E-1.4 REAGENTS Calcium Sulphate anhydrous. anhydrous. anhydrous. TO SALT WATER Magnesium Magnesium Sodium Chloride Sulphate Chloride *Methods of test for ready mixed paints and enamels ( second revision ). 11 Is: 8983 - 1978 E-2. PROCEDURE E-2.1 Prepare a panel as described in 5.2.1 brushing as prescribed Apply another coat of panel to the following of mild steel of approximately 150 X 150 X 1'25 mm of IS : lOl-1964*, and paint with the material by Stove the panel at 140°C for 23 minutes, in B-2. the material and stove as given above. Expose the cycle: in salt water of the following anhydrous anhydrous anydrous composition: 1.3 g 2'6 g l-7 g 21'4 g 1 000 ml outside at an angle and till the commencement of of 45" facing south, a) One hour immersion .I) Calcium sulphate, 2) Magnesium 0s Magnesium 4) Sodium 5) Water b) Three c) chloride, sulphate, chloride to make hour exposure One hour refrigeration at 4 & 2X, d) Exposure outside the next cycle. E-2.2 Repeat the during each cycle. the paint film. at 45" facing south cycle 12 times exposing the same side of the panel Examine the exposed side for signs of breakdown of APPENDIX [ Table 1, Item (xvi) TEST F-l. F-l.1 F-2. F ] FOR DURABILITY PREPARATION Prepare OF PANEL in E-2.1. the panel as described PROCEDURE F-2.1 Expose the painted panels, in duplicate, outdoors for 6 months at At the end of the period examine the test an angle of 45" facing south. panels under x 10 magnification. The material shall be taken to have passed the durability test if there is no sign of checking, brittleness or other impairment of film integrity, not more than a trace of chalking and no appreciable fading/darkening or change of colour and loss of gloss. *Methods of test for ready mixed paints and enamels ( second revision ). 12 IS : 8983 - 1978 In this respect the sample shall not be inferior to the approved when tested in the similar manner and at the same time. NOTE Provisional acceptance may be given on one month exposure sample set of painted panels as follows, but the durability of the material be taken only after 6 months exposure as above. The painted panel shall be exposed outdoors for 25 days at an angle of 45" facing south. At the end of this period the panel shall be subjected ( A suitable to a fine spray of water for 6 hours at a temperature not above 30°C. spray is provided by a water supply at a pressure of approximately 13.7 KPa through a rose ). The treatment shall be carried out daily for six days. The test panels shalt be exposed at an angle of 45' facing south between treatment. on separate APPENDIX G [ Table 1, lTtem (xviii) ] DETERMINATION G-l. G-1.1 G-l.2 G-l.3 G-l.4 REAGENTS Dilute Hydrochloric Acid gas. Solution saturated. Solution O-1 N 1 : 1 ( v/v ). 20 percent. OF CALCIUM COMPOUNDS Ammonium Hydrogen Ammonium Hydroxide Sulphide Oxalate - G-l.5 Standard Potassium ( see 27 of IS : 2316-1968* ). G-1.6 G-l.7 G-2. Concentrated Ammonium PROCEDURE Nitric Chloride Permanganate Acid G-2.1 Weigh accurately about 0'5 g of the extracted pigment in a 250-ml Add 50 ml of dilute hydrochloric acid and boil gently for about beaker. Dilute the solution to about 200 ml with water and boil again 5 minutes. Place the beaker on a water-bath and boil for about 2 to for 2 minutes. Filter the hot solution through a filter paper (Whatman No, 30 3 hours. or equivalent ) and wash the residue with hot water till the filtrate is free from chloride and lead ions. G-2.2 Treat the filtrate obtained in G-2.1 with a few drops of concenAdd about 5 g of ammonium chloride and trated nitric acid and boil. hydroxide. Boil for make the solution alkaline with ammonium Wash the precipitate with 15 minutes and filter through a filter paper. *Methods of preparation analysis (Jirrt revision ). of standard solutions for calorimetric and volumetric 13 IS:8983 - 1978 water and then pass a stream of hydrogen sulphide gas through the filtrate for 15 minutes. Filter off the sulphide and wash 2 to 3 times with Boil the filtrate to remove saturated solution of hydrogen sulphide. boiling after acidifying the solution. hydrogen sulphide and continue Make the solution alkaline to litmus with ammonium hydroxide and heat Add sufficient quantity of ammonium oxalate solution and boil to boil. for 5 minutes. Allow the beaker with the precipitate to stand for 2 hours Filter the residue through a filter paper water-bath. and wash several times with hot water. :&hat a man No. 90 or equivalent) Ignite it in a porcelain crucible to calcium oxide, cool in a desiccator and weigh to constant mass. 6-2.3 Alternatively, wash the residue on the filter paper with hot water until the filtrate is free from oxalate ions. Wash down the residue on the filter paper into the original beaker with hot water and wash the filter paper with dilute sulphuric acid and collect the washings in the beaker. Heat to about 70 to 80°C and titrate with standard potassium permanganate solution. When the end point is reached, put the filter paper on which the precipitate was washed in the beaker and complete the titration by adding further quantity of permanganate solution. ( For filter paper not more than two drops of standard potassium permanganate need be required. ) G-3. G-3.1 CALCULATION Ignition Method oxide, percent by mass = 100 X - Ml Calcium where MZ M, = mass in g of the calcium MS = mass in g of the pigment ~6-3.2 Titration Method oxide, percent oxide obtained, and taken for analysis. Calcium where V = Jv = M2 = by mass = 2.8 `v Jv M2 volume solution, normality in ml of standard potassium permanganate and of potassium permanganate solution, mass in g of the pigment 14 taken for the analysis. ISr8983-1978 [ APPENDIX H Table I, Item (xix) ] OF BARIUM SULPHATE DETERMINATION H-l. H-l.1 H-l.2 H-l.3 H-l.4 H-l.5 H-l.6 REAGENTS Sodium Sodium Dilutd Carbonate Carbonate Hydrochloric - anhydrous. 2 g/l. Solution Acid - 1 : 4. ( m/m ). SeeIS : 265-I 976*. Ammonium Concentrated Dilute Nitric Hydroxide 20 percent Acid - Hydrochloric Acid - 1 : 1 ( u/v ). Solution Dissolve 0.1 g of methyl H-l.7 Methyl Orange Indicator orange in 100 ml of water. H-l.8 H-2. Ammonium PROCEDURE Sulphate Solution - 3 percent. H-2.1 Weigh about 1 g of the extracted pigment in a dry and clean Cover the beaker and 250 ml beaker. Add 20 ml of dilute nitric acid. Dilute the contents to about digest it over hot plate for one hour. wash the insoluble residue several 150 ml, filter through filter paper, Cool it and add about Ignite the residue in platinum crucible. times. 8 g of anhydrous sodium carbonate and cover the crucible. Fuse the The fusion is started with mixture over a Meker burner for 40 minutes. This precaution is a low flame which is gradually raised to full blast. necessary to prevent loss due to overflowing. H-2.2 Cool and as the melt cools, rotate the crucible so that the fused mass solidifies in a thin layer. This will shorten the time required for Leach out the fusion with 200 ml of hot water in a 400-ml leaching. Filter through a 15 cm filter paper (Whatman No. 40 or beaker. Wash several times by decantation, then remove the equivalent ). crucible from the beaker, transfer the insoluble carbonates to the filter, and wash with hot sodium carbonate solution, testing after the twelfth washing to be certain that sulphates have been removed completely. *Specification for hydrochloric acid ( second revision ). 15 IS : 8983 - 1978 H-2.3 Cover the funnel containing the insoluble carbonates tiith a watch-glass and add hot dilute hydrochloric acid carefully, in small portions at a time to prevent loss, catching the solution in a 600-ml beaker. Add hot dilute hydrochloric acid to the platinum crucible and the beaker in which the leach was made and pour over the filter. Wash the paper with hot water until free from chlorides. H-2.4 Neutralize this solution with ammonium hydroxide using methyl orange as indicator. Add 0.4 to 0.6 ml of concentrated hydrochloric acid. Dilute to 400 ml of with hot water, bring the solution to boiling, and add 25 ml hot ammonium sulphate solution dropwise with constant stirring to prevent co-precipitation of calcium and magnesium. Transfer the beaker to a warm hot plate and allow to stand for at least 4 hours. Filter on an ignited weighed Gooch crucible, wash with hot water several times by decantation. The beaker should be scrubbed thoroughly to remove any adhering precipitate. Continue the washing until free of chlorides. Ignite the crucible in a muffle furnace for 35 minutes at 850°C. Cool in a desiccator and weigh. Make a blank determination in a similar manner with an equal amount of sodium carbonate and other reagents. H-3. CALCULATION Barium where sulphate, percent by mass = 100 (A--B) M A = mass in g of the precipitate with the material, in the taken blank determination, B = mass in g of the precipitate and M = mass in g of the material for the test. 16